Sapling #3
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Sapling #3
I am still struggling to understand how to draw Lewis structures that "minimize formal charge." What is the best way to approach these types of problems?
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Re: Sapling #3
I calculate the formal charge of each element in a bond and try to get the charge to be as close to 0 as possible using the formula Valence electrons-(lone pairs+ shared electrons/2).
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Re: Sapling #3
Hi Shannon!
Personally, I draw out the lewis structure first with just single bonds, then calculate formal charge using the forumla Valence E-(shared/2 +Lone E-). If I find that there is a formal charge higher than 0, I then start to add double bonds if necessary. It's kind of like a guess and check type of thing. Formal charge will always be your best indicator!
Hope this helps!
Personally, I draw out the lewis structure first with just single bonds, then calculate formal charge using the forumla Valence E-(shared/2 +Lone E-). If I find that there is a formal charge higher than 0, I then start to add double bonds if necessary. It's kind of like a guess and check type of thing. Formal charge will always be your best indicator!
Hope this helps!
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Re: Sapling #3
Shannon Moore 2L wrote:I am still struggling to understand how to draw Lewis structures that "minimize formal charge." What is the best way to approach these types of problems?
I'm having similar struggles and also assigning the formal charge is challenging for me on sapling. Does anyone know how to assign the formal charge with the sapling tools?
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Re: Sapling #3
The best way to understand and easily draw Lewis Structures is by practicing a ton! Through practice, you will understand how many bonds each element usually likes and be able to draw the least charged molecule. Understanding that N likes 3 bonds, O likes 2 bonds, Carbon likes 4, and Hydrogen likes 1, and halogens usually only like one, you can more easily determine how to draw structures with the lowest/zero formal charge.
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Re: Sapling #3
This is how I do it
I draw the lewis structures with single bonds first and calculate the formal charge. If there are any formal charge that is higher than 0, that's when I add double bonds.
I draw the lewis structures with single bonds first and calculate the formal charge. If there are any formal charge that is higher than 0, that's when I add double bonds.
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Re: Sapling #3
For the most part its guess and check work which can get tedious, but just use the formula charge equation to help if you need. The more you do the better you will get at them so don't worry! You got it.
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Re: Sapling #3
If you haven't seen the video called Bonding Models and Lewis Structures: Crash Course Chemistry #24 by Crash Course on YouTube, you should check it out! It helped me a lot!
https://www.youtube.com/watch?v=a8LF7JEb0IA
https://www.youtube.com/watch?v=a8LF7JEb0IA
Re: Sapling #3
Honestly, I would say start with the minimum (single bonds) and then if necessary just guess and check till you get the lowest possible formal charge for all your elements. I do not think there is a shortcut for this.
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Re: Sapling #3
AlyssaMaynard1C wrote:Shannon Moore 2L wrote:I am still struggling to understand how to draw Lewis structures that "minimize formal charge." What is the best way to approach these types of problems?
I'm having similar struggles and also assigning the formal charge is challenging for me on sapling. Does anyone know how to assign the formal charge with the sapling tools?
To assign the formal charge on Sapling, select More and there will be + and - buttons. You also click on the one you want this charge to be added to. Also, the more times you click + or -, the more it will add. For example, click - twice to get 2-.
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Re: Sapling #3
So what helped me the most was drawing different structures and calculating the formal charges for each atom in each configuration. It takes me a little while to do it but it's the most reliable way I've found!
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